1. Field of the Invention
This invention relates to a rotor of a built-in motor. More specifically, this invention relates to an improvement applicable to the structure of a rotor of a built-in motor, for the purpose of enabling the shaft of the built-in motor to be readily removed from the core of the built-in motor.
2. Description of the Related Art
It is not necessarily difficult to fit the shaft of an electric motor with the core of the electric motor, because various convenient methods, such as force fit, shrinkage fit, etc., are available. It is not necessarily easy, however, to remove the shaft of an electric motor from the core of the electric motor, because application of a considerable magnitude of heat, pressure or the like is generally required for this purpose.
Since a built-in motor has a stator which is mounted, with a flange, on a machine which is driven by the built-in motor, and since it has a rotor which is fitted with the shaft of the machine which is driven by the built-in motor, the core is inclined to be frequently required to be removed from the shaft.
Therefore, a structure which allows a shaft to be readily removed from a core is desirable for a built-in motor.